The solid-liquid transition in complex fluids

TL;DR

This paper investigates the yielding behavior of various soft materials like foams and emulsions, proposing that their strain-dependent shear modulus results from a universal elasto-plastic response mechanism.

Contribution

It provides a unifying interpretation of the strain dependence of the shear modulus across different complex fluids based on elasto-plasticity theory.

Findings

Strain dependence of shear modulus is similar across diverse materials.

Elasto-plastic response explains the observed mechanical behavior.

Supports the idea of a universal yielding mechanism in soft materials.

Abstract

The yielding of foams, concentrated emulsions, pastes and other soft materials under applied strain is often characterized by measuring the complex shear modulus as a function of strain amplitude at low frequency. Results obtained for materials of different physico-chemical constitution are strikingly similar, suggesting the presence of a generic mechanism as pointed out in several previous theoretical studies. We show that the observed strain dependence of the complex shear modulus can be interpreted as the consequence of elasto-plastic response.